Automatic spiraling device for aircraft



Dec. 29, 1936. M. F. BATES AUTOMATIC SPIRALING DEVICE FOR AIRCRAFT Filed April 2'7, 1954 3 Sheets-Sheet l INVENTOR ORTIMER F BATES Dec. 29, 1936.

M. F. BATES AUTOMATIC SPIRALING DEVICE FOR AIRCRAFT Filed April 27, 1934 3 Sheets-Sheet 2 INVENTOR MQHT/MER E H755 H/fi ATTORNEY Dec. 29, 1936. M. F. BATES 2,066,194

AUTOMATIC SPIRALING DEVICE FOR AIRCRAFT Filed April 27, 1954 s Sheets-Sheet s INVENTOR NgRT/MER F 59755 HIS ATTORNEY.

Patented Dec. 29, 1936 I AUTOMATIC SPIRALING DEVICE FOR AIRCRAFT Mortimer F. Bates, Brooklyn, N. Y., assignor to Y Sperry Gyroscope Company, 1110., Brooklyn, N. Y., a corporation of New York Application April 27, 1934, Serial No. 722,703

. 15 Claims. (Cl. 244- 77) This invention relates to automatic pilots for lar air pick-01f devices 6 and 1, respectively. Owaircraft and more particularly to a means for ing to the fact that the directional gyroscope has causing automatic or semi-automatic ascent or a tendency to wander, I prefer to supplement descent of the plane in a spiral or helical path. the action thereofby a magnetic compass, as out- By means of my invention the aircraftmay be lined in my aforesaid prior Patent #2,003,270. 5 caused to spiral upward, for instance, at the Such a compass element is shown at 8, said elewill of the aviator and to straighten out on a ment positioning an air jet 9 which acts on balpredetermined course. If desired, both the numanced paddles l0 and H to close one or the ber of spirals and the course of the airplane other of opposite pairs of contacts 12 and I3,

may be set before leaving the ground, so that depending on which way the air jet moves. The 10 the pilot may be used on a craft without any contacts act through relay coils l4 and I5, rehuman pilot. Preferably I accomplish the conspectively, to close contacts l6 and I! for drivtrol through the same directional gyroscope used ing the follow-up or azimuth compass motor It! for automatically steering the craft on a straight in one direction or the other, depending on which 15 course. When so used, the gyroscope is prefercontact is closed. Said motor rotates the com- 5 ably supplemented by a magnetic compass to corpass bowl through worm l9 and worm wheel root for wandering, as generally outlined in appliand also rotates the arm 2|, through a slip cants prior application for Follow-up systems friction mounting on the shaft 22 of the comfor magnetic compasses, now Patent #2,003,270, pass bowl, thus closing one or the other of opdated May 28, 1935. When it is desired to turn, posite pairs of contacts 23 or 24.

however, the supplemental control of the gyro- These last named contacts operate, respectivescope may be transferred from the magnetic comly, relay coils 25 and 26, which operate contacts pass to a turn device which, operating through 21 and 28 for normally controlling the motor 29 the gyroscope, causes the aircraft to turn at a adjacent the directional gyroscope. Said motor 25 variable rate depending on the setting of the deoperates through large ratio reduction gearing 25 vice. Preferably, also, there is incorporated 30, 3| to turn the shaft 32, which sets the course therewith an automatic banking arrangement on the gyroscope. Said shaft is shown as havto bank the craft at the proper angle for the ing a friction clutch 33 thereon, coupling the rate of turn. During the turn the craft may be e 0, gear 3 meshing With a gear 5 0 caused to climb through the automatic pilot or the top of the gyroscope. The rotation of said 30 otherwise. gear 35 turns the air pick-off devices 4 with Referring to the drawings illustrating several reference to the air cut-ofi? disc 36, as more forms my invention may assume, completely described in the aforesaid Patent Fig. 1 is a diagram with wiring connections, #1,992,970, so that the general course is under 35 showing the layout of the various elements of the control of the magnetic compass, but tem- 35 my invention. porary deviations of the magnetic compass do not Fig. 2 is a similar diagram of a modification affect the same unless they exceed the angular which may be used with complete automatic play or loss motion provided between arm 2| and flight. contacts 23, 24, and also owing to the slow rate Figs. 3 and 4 are details of the air pick-off that the contacts are turned from the magnetic device used on the type of gyroscopes shown. compass. It should also be noted that the mag- My invention is illustrated as applied to the netic compass is cut out entirely when the craft general form of aircraft automatic pilot disis turned, which is the time that'it is subject closed in my prior joint application, together with to the most serious deviations. Elmer A. Sperry, Jr. and Bert G. Carlson, on Auto- Preferably I bring in the automatic turn device matic pilots for aircraft, now Patent #1,992,970, through the same motor 29. To bring the same dated March 5, 1935. According to this sysinto action I show a throw-over switch 40 having temthe aircraft is controlled inazimuth from a a plurality of .contact arms 4|, 42 and 43 condirectional gyroscope I which governs the, rudnected therewith. When said switch is inthe der'2 through a servo-motor 3 controlled from a position shown in Fig. 1, namely, in position 0, 50 suitable air pick-off device 4 (see Figs. 2, 3 and 4) the magnet c pa s n control of the motor on the gyroscope. Similarly the ailerons and 29, because the switches 44 and 45 are closed elevator are" controlled from a gyroscopic horiby the arms 4| and 42, respectively, at that time, zon 5 (Fig. 1) which controls the aileron and while the switch 46 is ope When. however, elevator servo-motors (not shown) through simithe switch is thrown to the positi n T, contacts 55 gearing II and I2 and shaft 81.

44 and 45 are broken and contacts 44', 45' and 48 are made. This severs the connection of motor 28 with the magnetic compass control and connects it to a pair of potentlometers 48 and 48. The movable arms 48' and 48' of said potentiometers are shown as mounted on the shaft 58 of the turn knob or handle 5| and are in the armature circuit of motor 28. When said arms are in the central position, the motor 28 stands still as the current potential is balanced through the armature. When, however, the knob is turned to the left, the motor will be caused to run slowly in a direction to cause the airplane to turn left at the desired rate as long as the handle 5| is held to the left in a fixed position, and vice versa when the arm is turned to the right. The rate of turn may be varied by varying the amount that the handle is turned in either direction, thereby varying the position of the arms 48, 48' on the potentiometers 48, 48. Preferably, however, the motor is always run at a slow speed not to exceed the maximum rate of turn of the craft.

Preferably, means are also provided to cause proper banking of the plane at the same time. To this end, movement of said arm also turns the cam disc 52 connected therewith. Such movement first pulls the L-shaped lever 58 to the right or left, dependent on which way the disc is turned, and then forces.it downwardly out of the notch 54, thus turning the support 55 of the mercury pendulums 58, 58 about the pivot 51 in one direction or ,the other. Said pendulums may be adjusted by turning the knob 58, which is reversely connected to the two pendulums. Each pendulum is pivoted about a center 88, 88' and has a limited amount of mercury 8| in a U-shaped tube in the base thereof and a single contact 82, 88 at the opposite end of each tube.

During normal level flight the mercury does not touch the contact 82 or 88 in either tube.- When turning, however, centrifugal force will cause the mercury in the tube on the outside ofthe curve to contact with the flxed contacttherein. Normally these contacts are dead, but when the throw-over switch 5| is thrown'to the right or left the contacts are energized through contact 81 as hereinafter described, so that when the mercury contacts with one or the other, one or the .other of the bank motor relay magnets 84 and 85 is energized to close the circuit to the armature of the bank motor 88 to turn it in the proper direction to bank the plane until the mercury contact is broken. Tilting the member 55 initiates the bank prior to the turn and also insures the correct banking angle by eliminating the lost motion between the mercury and the contact.

Banking is shown as accomplished through the artificial horizon 5 by means of the same shaft 81, normally used for manually causing banking through the knob 88. As shown, a friction clutch 88 may also be provided between the gear I8 driven from the motor 88 through the reduction Said shaft is shown as provided with a gear 18. meshing with a segment I4 which turns the air nozzle member 8 about the fore and aft axis of the gyroscope and with reference to thecut-ofl disc I5 thereon (see also Fig. 4). The follow-up from the aileron servo-motor is shown as coming in through a cord or belt ll, pulley l8 and differential 18, similar to follow-up cord ll, pulley 18 and differential 18 on the directional gyroscope.

The disc 52 is also preferably provided with a second notch 88 so that when it is turned it forces the rod 8| to the right to bring into action mechanism for rendering the automatic banking contacts operative and also for restoring the contacts to the normal or level flying condition upon completion of a turn. When said rod 8| is forced to the right, the roller 82 'on the end thereof lifts the slide 83, thereby disengaging notch 84 in the base thereof from a pin 85 on a traveling nut 88. The raising of said slide also causes contact 81 to energize the mercury contacts and also lifts pin 88 out of a notch in a collar 88 on shaft 88, which is threaded in said nut 88. Said shaft is rotated from the banking motor 88 through connecting shafts 8| so that as said motor rotates, the nut 88 travels to the right or left and breaks one or the other of normally closed contacts 82, 88 to act as means for limiting the amount of bank. The simultaneous climbing of the craft to produce a spiral may be controlled by thumb piece 85, which shifts the relative position of nozzle member 1 through worm 88.

When the turn is complete and it is desired to straighten out the craft on its flnal course, lever 5| .is moved to its switch 48 is moved to the left, thus causing the motor 28 to be controlled from the magnetic compass. As the turning ceases, centrifugal force mid position and the bank motor with the part 8 in its normal position for level flight.

An interlock may begprovided between controllers 48 and 5| to prevent the former being moved from the turn to the straight flight position until the latter is centralized and to lock the latter when the former is in the straight flight position. This is shown in the form of a spring pressed pin 81 which, when handle 48 is'turned to T, drops in a notch 81'. At its outer end said pin, in the position shown in Fig. 1, bears against a flattened side of cam disc 88 on shaft 58, but when pin 81 drops in notch 81, handle be turned. Conversely, when ,said handle is turned to the right or left, handle 48 is locked by pin 81 in notch 81'.

It is obvious that the change of course may be effected through the gyroscope in other ways than that illustrated. Thus, instead of using the motor 28 to turn the controller alone, it may be used as a torque device 28', as shown in Fig. 3, to apply a weak torque about the horizontal axis of the gyroscope I to cause slow precession in azimuth, as outlined in the prior patent to Elmer A. Sperry, Jr., No. 1,982,702, dated December 4, 1934, for Gyro-pilots for aircraft. In either case the effect is the same, and the magnetic compass may be used to prevent deviation due to the tendency of the gyroscope to wander.

It is obvious that my invention may also be applied to a completely automatic pilot which may be flown without a human pilot. Fig. 2 illustrates one method of modifying the device to this end; the corresponding parts being correspond- 8 numbered. In this figure only the directional gyroscope control is illustrated, it being understood that the horizon gyroscope control may remain as shown in the other figure. Also complete automatic control, such as the height control meansfor controlling the height at which the plane flies, etc., these elements being known in the prior art.

According to this form of the invention, the number of spirals made by the craft isunder the control of a timing or counting mechanism or remote control device I00 which may be set to start the spiraling operation within a predetermined time after launching. The timing mechanism throws double pole, double throw switch-IOI in one direction or the other, depending on in which direction it is set for spiraling. This operation starts the motor I02, through interlocking relay I25 in the proper direction, which turns the disc 52' and its shaft 50' to move the rheostat arms 48', 49' to the right or left, as in Fig.1. 3 The turning of the disc may operate the same parts as shown by the similar numerals in Fig. 1 and may also turn a disc I20 on shaft 50' to throw switch 40 to the turn position through a latch I2 I. Disc 52' also pushes to the left a rod I03 to close a switch I04 in the armature circuit of the motor I02. Said switch is also closed by the excitation of electromagnet I05 in series with contacts I00, I01 at switch IN. The purpose of this switch is to,cause the motor I02 to run the disc 52 back to its central position when switch IN is open.

The motor 29 is brought into acton as before to turn the follow-up system 35 on the gyro slowly and continuously, and-the throwing of the switch 40 to the position T operates the motor through the Wheatstone bridge resistances 4 8 and 49 as before. The motor is shown as connected to the shaft 32' through a worm I08 and a worm wheel I09. Loosel'y mounted on shaft 32' is a notched disc 0 which is clutched to said shaft through jaw clutch III. Said clutch is spring engaged and may be under the control of electromagnet I I2, the circuit through which is broken when the switch 40 is on position T. It should also be noted that the field of themotor 29 is placed in a circuit with switch H3, which is open when the pawl I I4 engages the notch H5 therein and when electromagnet H6 is de-energized. When, however, magnet IIB is energized by the closing of switch I06, I07, or when the disc H0 is turned so that said pawl does not engage said notch, switch H3 will remain closed. This ,insures the disc, now clutched to the shaft, being brought back to the original starting position and terminates the spiral on the original heading, since the motor will keep running until the disc turns the notch H5 under the pawl H4. After the predetermined number of turns are completed, the clock. mechanism throws the switch l0l back to the off position. Thus the craft will straighten out, on its originally setcourse. It will be understood that the automatic climb mechanism (not shown) should be synchronously thrown out, preferably by the same timing mechanism I00 or by a height responsive means, referred to above as known per se in the prior art. See patent to Lawrence B. Sperry, No. 1,418,605, dated June 6, 1922, for aerial torpedoes. Since the rate of climb is known, the height to which the plane will climb in a predetermined time or number of turns can be predetermined.

In accordance with the provisions of the patent statutes, I have herein described the principle and operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means. Also, while it is designed to use the various features and elements in the combination and relations described, some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. In an automatic pilot for aircraft, the combination with a directional base line, a servo-motor and a rudder, of control elements actuated by said base line and servo-motor, the relative position of which governs the servo-motor, motive means for continuously shifting the relative position of said elements, whereby a continuous turn. is caused, and means for varying the rate of turn at will.

2. In a spiraling device for aircraft automatic pilots, the combination with directional and horizon gyroscopes, servo-motors and rudders, of control elements actuated by each and their respec-- tive servo-motors, for. governing the steering,

banking and elevator servo-motors, means for altering the relativeposition of the horizon elements to cause banking, climbing or diving, means for slowly and continuously'shifting the relative 'position of said directional elements, whereby spiraling is caused, a level device for detecting turning, and means controlled thereby for altering the relative position of said horizon elements to cause banking at the proper angle during a urn.

3. In an automatic pilot for aircraft, the combination with a directional gyroscope, a servomotor and a rudder, of control elements actuated by said gyroscope and servo-motor, the relative position of which governs the servo-motor, a magnetic compass for normally preventing any wandering tendency of said gyroscope from causing deviation from course, a manually controlled device for causing turning of the craft through said gyroscope, and means for transferring the control of said gyroscopic control elements from said magnetic compass to said manual means at w' l.

4. In an automatic pilot for aircraft, the combination with a directional gyroscope, a servomotor and a rudder, of control elements actuated by said gyroscope and servo-motonthe relative position of which governs the servo-motor, a magnetic compass for shifting the relative position of bination with'a directional base line, a servo-mo g0 tor and a rudder, of control elements actuated by said base line and servo-motor, the relative position of which governs the servo-motor, motive means for continuously shifting the relative position of said elements, whereby a continuous turn is caused, turn detecting means and means brought into action by the actuation of said turn detecting means for causing automatic banking of the craft during a turn at the correct banking angle.

6. In an automatic pilot for aircraft, the combination with directional and horizon gyroscope's, servo-motors and rudders, of control elements actuated by each and their respective servo-motors, means operable at will for continuously shifting the relative position of said directional elements to cause turning, normally inoperative .turn detecting means, means brought into operationbysaidilrstnamedmeansiorrendering said means'operative, and means controlled by said turn detecting means Ioraltering the relative position of thehorimn elements to cause proper at an angle proportional to the rate of turn. 1

' 7. An automatic pilot as claimed in claim 6, in which means are provided for throwing out said turndetecting meansto eliminate the I andbrlngthecraft'backtoite level position when the turn is stopped.

8. In an automatic pilot ior aircraft, the comtion witha gyroscope, a servo.- in and a rudder, 0! control elements actuated by' said gyrowope and servo-motor, the. relative position a which governs the servo-motor,-, a magnetic compo-m for normally preventing any wandering tendency oi said gyroscope from .causing deviation from course, a manually controlled device for calming turning of the craft through said gyroscope, motive means torslowly turning said elements with respect to said gyroscope, and means for governing said motive means either from said compass or said device at will.

9. In an automatic pilot for aircraft, the combination with directional andstabiiizing base lines and servo-motors, oi azimuth and elevation conm1 elements actuated by said base lines, and

servo-motors, the relative position of which governs the servo-motors, means for setting the elevation control element to cause climbing, motive means for continuously shifting the relativeposi tion oi'said azimuth control elements, whereby a continuous turn is caused, and automatic means for throwing out said turn and climb means after a predetermined number of turns has been made, wherebythecrattmaybecausedtospiral upward to a predetermined height and then to straighten out on its predetermined level course.

10. In a navigational device for aircraft, a

gyroscope by which the course is normally maintained, a magnetic compass, means actuated thereby for preventing deviation due to wandering of the gyroscope, means for causing turning of the craft through said gyroscope, and means for rendering said compass actuated means inoperative while said last named means '11.;In pilot roiaircrait, the

trol elements in their origithe turn is completed, cratt' will iiy'on the originally set steering device for dlrig ible vehiclu, the combination with a lree gyro 9 a magnetic compare and a controller normaiiy control or both-said gyroscope compass, of means for preventing saidcoin- 7 connections between compass and controller during a turn? 13. In an automatic steering device for dirigible Tvehioles, the combination with a tree gyrothree degree of freedom type and a magnetic compass, both oi which normally operate to gether to control said means, and-means ior relative position of said elements at a uniform" rate,-whereby a continuous turn at a constant rate is caused. i

1 MORTIMER r. BATES. 

